One in ten car crashes on the highway is the result of drowsy driving, according to AAA.

The travel and insurance group recently conducted the most in-depth drowsy driving research ever done in the U.S.

AAA based its study on dashboard videos from 700 accidents.

It revealed drowsy drivers were involved in 9.5 percent of all crashes. Federal estimates previously indicated drowsiness was a factor in only one to two percent of crashes.

"I'm a little shocked," said Bobbi Nunn. "I would think it would be more alcohol or drug-related but I can definitely see where it could be a disadvantage when you're driving while tired."

The California Highway Patrol says drowsy driving can be as dangerous, if not more so, than driving under the influence.

"If you're asleep for 1.5 seconds at 65 miles per hour, you're going to travel the length of a football field and wake up not evening knowing where you're at," said Officer Jordan Richards, California Highway Patrol.

Officer Richards says it's not abnormal to find people too tired to be driving on local roads.

The Centers or Disease Control and Prevention says 35 percent of U.S. drivers sleep less than the recommended minimum of seven hours a day.

Yvonne Johnson and her husband recently made the drive from North Dakota to Pismo Beach.

"We start pretty early in the day, like around 8, and get out of the car every couple hours and walk around," Johnson said.

Bobbi Nunn of San Diego drives to Arizona a lot.

"Usually, if I get sleepy, I just open up the window and I chew on peppermint gum or have mints because peppermint, the oils and the smell, seems to revive me," Nunn said.

AAA also recommends that drivers travel at times of day when they are normally awake, avoid heavy foods and avoid medications that cause drowsiness or other impairment.

AAA adds that missing just a few hours of sleep can more than quadruple your chances of getting in a crash.

More than 3,500 drivers from across the U.S. were surveyed for the study.